Grinding machine



June 16, 11936.

Filed oct. 15, 1951 M. CARTER RINDING MACHINE m El y 2 Sheets-Sheet 1 M. CARTER 2,0445@ GRINDING MACHINE Filed 001'.. 15, 1951 2 Sheets-Sheet 2 Patented June 16, 1936 UNITED GRINDING MACHINE Mitchell Carter, Los Angeles, Calif., assignor to General Electric Company, a corporation of New York Application October 15, 1931, Serial No. 568,890

10 Claims.

Thisv invention relates to grinding machines, and pertains more particularly to machines for grinding and disposing of refuse material such as garbage.

'Ihe disposal of garbage has long been a problem, not only to municipal authorities, but also to the average householder. From the standpoint of municipal authorities, the collection and sanitary disposal of g-arbage is becoming increasingly expensive and diicult. From the standpoint of the individual householder, the disposal of garbage has always been an unpleasant burden.

The invention to be describedl hereinafter proceeds on the theory that the proper method of garbage disposal is in the form of sewage passing through the usual drainage and sewer connections for disposal in the usual manner, or for reclaiming by known methods. To do this, however, presupposes the existence of a machine capable of reducing all kinds of garbage refuse to a suilciently comxninuted state to enable it to pass through drain and sewer pipes without danger of clogging the same. It is an object ofthe present invention to provide a satisfactory machine for this purpose.

Other objects `and advantages of the invention will appear hereinafter.

A preferred embodiment of the invention selected for purposes of illustration is shown in the accompanying drawings, in which,

Figure 1 is a vertical section through the machine.

Figure 2 is a section on the line 2--24 oi Figure 1.

Figure 3 is a section on the line 3--3 f Figure 2.

Figure llis a section on the line lof Figure 1.

Figure 5 is a section on the'llne of Figure 4.

Figure 6 is a section on the line 6-8 of Figure 3.

Figure 7 is a section on the line l-I of Figure 1.

Referring to the drawings, the apparatus comprises a casing I which forms a. receptacle 2 for the material to be ground. 'I'he saidcasing is preferably cylindrical in form and is closed at its upper end by a cover 3 having a locking connectlon of any suitable form such as the lug 4 which engages a suitable'groove in the upper edge of the casing so that the casing-may be tightly sealed.

Mounted within the casing I is a grinding member 5, preferably in the form of a disk having grinding teeth 8 on its upper surface, and having its outer periphery 1 positioned closelya terial between the grinding disk and the wall of the casing. In order to permit egress of ground material, the grinding disk itself is provided with a plurality of apertures, said apertures 8 being preferably of progressively increasing diameter from the grinding face of the disk to the opposite face in order to prevent any possibility of the said apertures becoming clogged with ground material. Preferably, the said apertures and teeth may be formed as illustrated in Figure '7, each tooth having an aperture associated therewith adjacent the cutting edge 9 in order that ground material may pass through the cutting disk immediately after being cut.

The grinding teeth and apertures illustrated may be conveniently formed by casting substantially cone-shaped projections on the grinding face and then drilling the cone-shaped apertures 8, the axes of the conical apertures being &- set somewhat from the axes of the conical projections in order that the cutting edge of each tooth may be near the apex of the cone-shaped projection illustrated in Figure 7.

It is desirable to prevent the teeth from grinding in xed grooves, and it is possible of course to prevent this by distributing the teeth at random over the surface of the grinding disk. It is desirable, however, to clean the grinding teeth continuously during the grinding operation, and accordingly, rather than arrange. the teeth at random it is preferable, for reasons which appear hereinafter, to arrange them in concentric circles, but about a center which is off-set from the center of rotation of the disk. This provides an eccentric motion of the grinding teeth which prevents any grooving of the material being ground.

As a convenient means of cleaning the grinding teeth, the scraper II (see Figures 2, 3, and

6) is provided having prongs l2 projecting between the rows of teeth and extending nearly to the surface of the .disk and adapted to dislodge any material tending to collect in the grooves between the teeth. As an additional cleaning means, the wire brush I3 may be secured to the scraper II to remove any material not removed by the prongs I2.

The scraper Il is held. against rotation, but ls permitted to reciprocate in order to accommodate itself to the .eccentricity of the grinding teeth. For this purpose the wall of the casing i is provided with a-ilongitudlnal groove I having a slide member ijtherein provided with a slot I'I adapted to recelvethe -iug I8 of the scraper. .The other end of the scraper Il is slidably mounted in the bevelled gibs I8 of the pivot member 20, and the said` member is rotatably secured 'to the grinding disk by means of the screw 2i. It will be observed that as the grinding diskis-rotated, the scraper is held from rotation by thesllde is grindingfteeth; kThe scraper also moves longitudinally ofthe receptacle with the grinding disk as the latter moves longitudinally as hereinafterl explained.

In order to rotate'the grinding disk 5 a drive shaft 23 is provided whichA has a screw thread engagement with the disk 5, and the said shaft is turned by a gear 24 driven by a worm 25 secured to the shaft 25 which may be rotated by any suitable source of power such as an electric motor (not shown).

In order to grind all of the material within the receptacle 2 and in order to maintain the desired grinding pressure thereon it is desirable to permit relative movement between the grinding disk and the casing, and this relative movement may be secured conveniently by permitting longitudinal movement of the grinding disk and the drive shalt. For this purpose the shaft 23 is preferably a square shaft, as illustrated, and is permitted to slide through the packing 25, through the hub of the gear 24 and through the packing 2t, the packings 23 and 2 3 being permitted to rotate as the shaft rotates. The packing 23'is held-in place by the washer 3| and nut 32,` whilethe packing 29 is held in place by bushings 33 and 34. The gear wheel 24 and worm 25 may be conveniently enclosed within a casing 35 which nay-be connected to the casing I by means of a plurality of brackets 31.

In order that the grinding disk may travel all the way to the top of the receptacle, so that all of the material therein may be ground, a groove 33 is cut in the cover 3 and is shaped to receive the scraper II and the member 2l. It desired the upper edge of 'the scraper may be serrated as at 3l.to 'cut through any material which may tend to lodge in the groove 3l.

Means are provided for reciprocating the grinding disk and shaft 23 and for applying pressure Ato the material being ground during the grinding operation. In this connection, it is pointed out that the grinding o f refuse material, such as garbage, presents an unusual problem -in that many' diil'erent kinds of material and materials diner-ing greatly in hardness and toughness must be ground.` For example, soft material such as bread or potato 'grind easily and quieiny so that a grinder or cutter may be fed quickly through them. On the other hand, materials such as bones are much harder to grind so that a grinder or cutter can be -fed through them but slowly. The feeding means for the grinder or cutter should meet all these conditions in a satisfactory manner, being fed forward in any instance at a rate depending upon the nature of the material being acted upon. Izhave found that a fluid pressure feed has substantial` advantages in the grinding of a material such as garbage'fsinee-ie feeds the grinding or cutting means forward at a speed responsive to the character of the mate'- rial being ground. Also, iluid pressure is advantageous because. it is always conveniently available.

In the preferred embodiment illustrated such fluid pressure. means. comprises a cylinder `43 which may depend from the casing 35 in position. to receive tneutwer end ofthe shaft n. A piston 4I is' mounted in the cylinder and is secured.

to the lower end of the shaft 23 by means of grooved packing 42 which is held in place by the bushing 43. thrust bearing 44 is moimted on the `upper face of thel'piston4l.

which may be connected to a suitable drain.

grindingdisktoitslower position. Q

It will be understoodthatthe invention may but is permitted to reciprocate as necessary to accommodate itself to the eccentricity of the" I'he upper end space 45 of the cylinder and the lower end space 45 are connected to a pressure supply line 41 by pipes 48 and 4l respectively and a four-way valve 5I) is interposed in said connection. The pipe 5I is also connected to said 5 valve and leads to a suitable drain. The fourway valve 53 is provided with passages 52 and 53 so that when it is in the position illustrated in Figure 1, the chamber 45 is connected tothe supply line 41 so that pressure is exerted on the up- 10 lper face of the piston thus tending to depress will connect the pipe 4| with-the supply line 41 thus exerting pressure-on the lower side of the piston 4I and tending to raise the same; At the 20 same time, the'pipe 45 will be connected with the drain pipe 5I thus permitting the uid con# tained in the chamber 45 to escape.y

If desired, in order to prevent application of excessive pressures to the grinding disk during 25 the grinding operation, a pressure relief valve 55 of any standard construction may be inserted in the pipe 4! in order that the pressure to be applied to the piston during its upward travel maybe set at any desired maximum. If this so maximum pressure is exceeded, the pressure will be relieved through the pipe 55 which-may also beconnectedtoadrain.

In order to provide fluid for flushing the ground material out of the lower part of the casing I, a 35 spray nozzle may be provided which may be connected through the pipe Il to the Supply line 41. The ground material andthe ilushing iiuid may pass from the casing I through the outlet 32 40 It may be desirable to provide automatic shutofi.' mechanism in order that operation of the grinder may be stopped when the grinding operation is completed. For this .purpose a collar 53 may be secured to the shaft 23 in position to en- 45 gage the trigger 54 when the grinding disk approaches its upper limit of motion. The trigger 34 is connected to a shaft 35 which extends through the wall of the cylinder' into proximity. with the electric switch 55 `which controls the 50 driving motor: As will be understood, a partial rotation of the shaft 55' will be sumcient to open the switch, thus stopping the electricmotor. At

the same time. it may be desirable to autimiatl-b Ashai't' 55. 'nie 'said valve is so arranged, thata partial mation of the snare-.lucani 'close the valve 51 thus shutting off the supply of water. As 604 lwill be understood, after the machine lis'thsls automatically shut off, it cannot Aagain be ed until the valve isoperatcd to restore bevariously modined within the scope of subjoined claims.

Iclaimasmyinvention: I l 1.4A grinding machine comprising a receptacle for the reception of material .70 tobeground, agrindingmeansin saidcylinder mounted for .rotationv inl a' planeV perpendicular to the axisof the cylinder', andmounted forrociprocation along a toethe axis of the cylinder., means forp mi said mea'srl-ior moving the grinding means for means, means for .moving said grinding means lengthwiseotf the cylinder, means controlled by automatically stopping the rotation of said' grinding means'upon completion of itslengthwise' travel Vin grinding direction, means forilushing the grinding in'ans, and controlling means for the flushing means Vactuated by the means for moving the grinding means.

2. A grinding machine comprising a cylindrical receptacle forrthe reception o f material to be ground, a grinding means in said cylinder, means for rotating said grinding means, means for moving said grinding means lengthwise of the cylinder. a water spray for flushing the ground material out of the bottom of the receptacle, and means controlled by said means for moving the grinding means for automatically stopping therotation of said grinding means upon completion of its lengthwise travel in grinding direction and for simultaneously automatically shutting oif said water spray.

3. A grinding machine for grinding garbage or the like comprising a receptacle, grinding means of an area equal substantially to the cross sectional area of the receptacle movable longitudinally of the receptacle whereby it compresses material to be ground against an end of the receptacle, a discharge opening for the receptacle, means for turning the grinding means, iluid pressure actuated means for effecting longitudinal movement o-f the grinding means, iiushing means for the grinding means, and valve means controlling the supply of fluid to the fluid pressure actuated means and to the iiushing means.

4. A grinding machine for grinding garbage or the like comprising a receptacle for the material to be ground, grinding means of an area equal -substantially to the cross sectional area of the receptacle movable from one end of the receptacle to the other whereby it compresses material to be ground against an end of the receptacle, a cylinder supported in iixed relation to the receptacle, a. piston in the cylinder, a rod connecting the piston to the grinding means, means for turning the grinding means, meansfor supplying water to the cylinder for feeding the cutting means axially into the cylinder, means for simultaneously supplying water to the grinding means for iiushing it, and a conduit connected to the receptacle for carrying away ground material.

5. A grinding machine for grinding garbage or the like comprising a cylindrical receptacle, grinding means of an area equal substantially to that of the receptacle which moves longitudinally of the receptacle and compresses the material to be ground against an end wall of the receptacle, said grinding means having openings through which ground material passes from the front of the grinding means to the rear thereof, and iiuid pressure actuated means for forcing the grinding means against the material to be cut with a. substantially constant pressure whereby movement of the grinding means is adapted to the varying nature oi the material being ground.

6. A grinding machine for grinding garbage or the like comprising a cylindrical receptacle, grinding means of an area equal substantially to that of the receptacle which moves longitudinally oi the receptacle and compresses the material to be ground against an end wall of the receptacle,

said grinding means having openings through which ground material passes from the front of the grinding means to the rear thereof, uid pressureactuated means for forcing the grinding means against the material to be ground with a substantially constant pressure whelieby movement of the grinding means is adapted to the varying nature of the material being ground, and means for supplying flushing Water to the rear surface of the grinding means for ushing away ground material.

7. A grinding machine for grinding garbage or the like comprising a receptacle, grinding means movable longitudinally of the receptacle, a discharge opening for the receptacle, means for turning the grinding means, iluid pressure actu- Iated means for effecting longitudinal movement of the grinding means, flushing means for the grinding means, valve means controlling the supply of uid to the iiuid pressure. actuated means and to the flushing means, and automatic means controlled by movement of the grinding means for stopping the rotation of the grinding means and cutting oi the flushing means.

8. A grinding machine for grinding garbage or the like comprising a receptacle for the material to be ground, grinding means movable from one end of the receptacle to the other, said grinding means having anarea equal substantially to the cross sectional area of the receptacle whereby it serves to compress material to be ground against an end of the receptacle, a cylinder supported in xed relation to thereceptaclaa piston in the cylinder, a rod connecting the piston to the grind- Iing means, means for turning the grinding means, 35

means for supplying iiuidA pressure to one end of the cylinder for feeding the grinding means axially into the cylinder, and means for supplying uid pressure to the other end of the cylinder for eiecting return movement of the cutting means.

9. In a grinding machine for garbage or the like including substances of different hardness, thecombination of a cylinder for the material to be ground, a grinding disk in the cylinder of a diameter equal substantially to that of the cylinder, uid pressure means for moving the disk along the axis of the cylinder to compress material to be ground between the disk and an end Wall of the cylinder, rows of outwardly projecting cutting teeth on the front side of said disk, and holes through the disk adjacent to said teeth for passage of ground material to the rear of the disk whereby the fluid pressure means causes relatively rapid axial movement when soft material is ground and slow movement when hard material is ground.

10. In a grinding machine for garbage or the like, the combination of a cylindrical receptacle, circular grinding means of an area equal substantially to the cross sectional area of the receptacle and movable longitudinally of the receptacle whereby it serves to compress material to be ground against'an end o f the receptacle, said grinding means being provided with openings for passage of ground material to the rear of the grinding means, fluid pressure actuated means for moving the grinding means longitudinally of the receptacle whereby a, substantially constant pressure is maintained for compressing the material to be ground against the end of the receptacle and means for rotating the grinding means.

' MITCHELL CARTER.. 

